[Libvir] virConnectOpenReadOnly broken
This is just a note that the following program tickles a nasty (memory corruptor?) bug somewhere in the open code. I'm still trying to look into the cause and will post a followup if I find the problem. Rich. #include <libvirt/libvirt.h> #include <stdlib.h> #include <assert.h> int main () { virConnectPtr conn; conn = virConnectOpenReadOnly ("xen+unix:///"); assert (conn); virConnectClose (conn); exit (0); } $ gcc -Wall test.c -lvirt -o test $ ./test libvir: Domain error : invalid domain pointer in virDomainFree test: test.c:11: main: Assertion `conn' failed. Aborted -- Richard Jones, Emerging Technologies, Red Hat http://et.redhat.com/~rjones virt-top is 'top' for virtual machines. Tiny program with many powerful monitoring features, net stats, disk stats, logging, etc. http://et.redhat.com/~rjones/virt-top
On Mon, Apr 07, 2008 at 03:00:52PM +0100, Richard W.M. Jones wrote:
$ ./test libvir: Domain error : invalid domain pointer in virDomainFree
Stranger and stranger is that I cannot reproduce this with libvirt from CVS, only with libvirt 0.4.1 in Fedora 8. However there is no change in either src/hash.c or src/libvirt.c that I can point to which could have fixed this. So I don't know if this bug has really been fixed or is just in hiding (evidence suggests that the F8 problem is caused by memory corruption, so this is exactly the sort of bug which might just disappear by a simple recompilation). Valgrind doesn't see anything. Rich. -- Richard Jones, Emerging Technologies, Red Hat http://et.redhat.com/~rjones virt-p2v converts physical machines to virtual machines. Boot with a live CD or over the network (PXE) and turn machines into Xen guests. http://et.redhat.com/~rjones/virt-p2v
On a different tack - what about making some Wiki pages, or the pages on the main site wiki-integrated? I would love to add more info for KVM users to the XML format page, there were a lot of things i had to trial and error figure out myself when importing a) DomUs from a past Xen Install and b) DomUs from kvm command-line only setups P.S. Do we say DomU in the libvirt/KVM world? :-) Thanks, Henri Richard W.M. Jones wrote:
On Mon, Apr 07, 2008 at 03:00:52PM +0100, Richard W.M. Jones wrote:
$ ./test libvir: Domain error : invalid domain pointer in virDomainFree
Stranger and stranger is that I cannot reproduce this with libvirt from CVS, only with libvirt 0.4.1 in Fedora 8.
However there is no change in either src/hash.c or src/libvirt.c that I can point to which could have fixed this. So I don't know if this bug has really been fixed or is just in hiding (evidence suggests that the F8 problem is caused by memory corruption, so this is exactly the sort of bug which might just disappear by a simple recompilation). Valgrind doesn't see anything.
Rich.
On Mon, Apr 07, 2008 at 04:03:25PM +0100, Henri Cook wrote:
On a different tack -
Please don't use 'Reply-To' for unrelated topic this breaks threading on intelligent mail clients.
what about making some Wiki pages, or the pages on the main site wiki-integrated? I would love to add more info for KVM users to the XML format page, there were a lot of things i had to trial and error figure out myself when importing a) DomUs from a past Xen Install and b) DomUs from kvm command-line only setups
My previous experience hosting a Wiki on xmlsoft.org (a.k.a. libvirt.org) has been rather painful, admitedly that was a few years ago ... I'm not sure what's the best way, hosting yet another wiki or reusing an existing one. I have a slight bias against Wiki for the following reasons: - you usually can't get the history - you can't ship the Wiki content with the releases (and I think packaging the information and the code together is fairly important) I understand that posting the data on the list for later integration in the docs may be a bit heavy, it introduces some kind of inertia against adding or updating, but the resulting information is more generally useful. That said I'm not against a Wiki, just a bit reluctant to maintaining it <grin/>
P.S. Do we say DomU in the libvirt/KVM world? :-)
I have tried to set up the terminology initially at the very beginning of the project see http://libvirt.org/intro.html the term is 'Hypervisor' it should be present though all docs and functions comments. Daniel -- Red Hat Virtualization group http://redhat.com/virtualization/ Daniel Veillard | virtualization library http://libvirt.org/ veillard@redhat.com | libxml GNOME XML XSLT toolkit http://xmlsoft.org/ http://veillard.com/ | Rpmfind RPM search engine http://rpmfind.net/
On Mon, Apr 07, 2008 at 11:47:37AM -0400, Daniel Veillard wrote:
My previous experience hosting a Wiki on xmlsoft.org (a.k.a. libvirt.org) has been rather painful, admitedly that was a few years ago ... I'm not sure what's the best way, hosting yet another wiki or reusing an existing one.
Wikis, as you point out, require active management. I'm running several low-traffic OCaml wikis (might as well advertise them: http://ocaml-tutorial.org/ and http://cocan.org/) with reasonable success. We require authenticated email addresses for all editing, a diff of all edits are CC'd daily to subscribers, and we have people who act as editors for particular pages / sections of the wiki. This has controlled spam reasonably successfully. One Ubuntu developer who shall remain nameless turned out to have a sideline in blackhat "SEO" (wiki spamming) and actually signed up with his valid email address to spam the wiki. This was spotted almost instantly and he was kicked off. We had another case where someone signed up using http://mailinator.com and set up a http://bugmenot.com account which we also found quickly and eliminated. The daily emailed diffs of the whole wiki, plus the ability to roll back a day, basically make any long-term wiki spam impossible to carry out (or so we think ...[1]) The benefits of all this management can be useful, user-driven resources, and _if_ carefully structured and edited, this can be better than Google + mailing lists or asking the same questions over and over on IRC. Just my 2p (about $1). Rich. [1] And if you think of a way, rather than making lots of work for our editors by "proving" it, just email me OK? -- Richard Jones, Emerging Technologies, Red Hat http://et.redhat.com/~rjones virt-p2v converts physical machines to virtual machines. Boot with a live CD or over the network (PXE) and turn machines into Xen guests. http://et.redhat.com/~rjones/virt-p2v
It sounds great, but is indeed a lot of maintenance. I'd like the chance to expand the xml section more for KVM users though! Perhaps just a definitive run down of all the possible XML options in a generic context. The rest of the project's obviously open source - is the website under a source tree? Can I come on board as a contributor in some sense and propose 'patches' for the site? Henri Richard W.M. Jones wrote:
On Mon, Apr 07, 2008 at 11:47:37AM -0400, Daniel Veillard wrote:
My previous experience hosting a Wiki on xmlsoft.org (a.k.a. libvirt.org) has been rather painful, admitedly that was a few years ago ... I'm not sure what's the best way, hosting yet another wiki or reusing an existing one.
Wikis, as you point out, require active management.
I'm running several low-traffic OCaml wikis (might as well advertise them: http://ocaml-tutorial.org/ and http://cocan.org/) with reasonable success. We require authenticated email addresses for all editing, a diff of all edits are CC'd daily to subscribers, and we have people who act as editors for particular pages / sections of the wiki.
This has controlled spam reasonably successfully. One Ubuntu developer who shall remain nameless turned out to have a sideline in blackhat "SEO" (wiki spamming) and actually signed up with his valid email address to spam the wiki. This was spotted almost instantly and he was kicked off. We had another case where someone signed up using http://mailinator.com and set up a http://bugmenot.com account which we also found quickly and eliminated. The daily emailed diffs of the whole wiki, plus the ability to roll back a day, basically make any long-term wiki spam impossible to carry out (or so we think ...[1])
The benefits of all this management can be useful, user-driven resources, and _if_ carefully structured and edited, this can be better than Google + mailing lists or asking the same questions over and over on IRC.
Just my 2p (about $1).
Rich.
[1] And if you think of a way, rather than making lots of work for our editors by "proving" it, just email me OK?
On Mon, Apr 07, 2008 at 06:38:18PM +0100, Henri Cook wrote:
It sounds great, but is indeed a lot of maintenance. I'd like the chance to expand the xml section more for KVM users though! Perhaps just a definitive run down of all the possible XML options in a generic context.
The rest of the project's obviously open source - is the website under a source tree? Can I come on board as a contributor in some sense and propose 'patches' for the site?
Yes, these are all in the source, under the docs/ directory (although the format is very confusing and it's often not clear what files are generated versus source files). IIRC in this case you have to edit docs/libvir.html. Rich. -- Richard Jones, Emerging Technologies, Red Hat http://et.redhat.com/~rjones virt-top is 'top' for virtual machines. Tiny program with many powerful monitoring features, net stats, disk stats, logging, etc. http://et.redhat.com/~rjones/virt-top
On Mon, Apr 07, 2008 at 05:38:48PM +0100, Richard W.M. Jones wrote:
On Mon, Apr 07, 2008 at 11:47:37AM -0400, Daniel Veillard wrote:
My previous experience hosting a Wiki on xmlsoft.org (a.k.a. libvirt.org) has been rather painful, admitedly that was a few years ago ... I'm not sure what's the best way, hosting yet another wiki or reusing an existing one.
Wikis, as you point out, require active management.
I'm running several low-traffic OCaml wikis (might as well advertise them: http://ocaml-tutorial.org/ and http://cocan.org/) with reasonable success. We require authenticated email addresses for all editing, a diff of all edits are CC'd daily to subscribers, and we have people who act as editors for particular pages / sections of the wiki.
This has controlled spam reasonably successfully. One Ubuntu developer who shall remain nameless turned out to have a sideline in blackhat "SEO" (wiki spamming) and actually signed up with his valid email address to spam the wiki. This was spotted almost instantly and he was kicked off. We had another case where someone signed up using http://mailinator.com and set up a http://bugmenot.com account which we also found quickly and eliminated. The daily emailed diffs of the whole wiki, plus the ability to roll back a day, basically make any long-term wiki spam impossible to carry out (or so we think ...[1])
The benefits of all this management can be useful, user-driven resources, and _if_ carefully structured and edited, this can be better than Google + mailing lists or asking the same questions over and over on IRC.
Well if you have maintainance experience, why not ... except libvirt.org is a RHEL-4 box, i.e. not the easiest for bleeding edge stuff. if you feel this is reasonnable, and won't waste too much time, I agree this can be really useful too, I'm fine with the idea. Daniel -- Red Hat Virtualization group http://redhat.com/virtualization/ Daniel Veillard | virtualization library http://libvirt.org/ veillard@redhat.com | libxml GNOME XML XSLT toolkit http://xmlsoft.org/ http://veillard.com/ | Rpmfind RPM search engine http://rpmfind.net/
I'd happily host wiki.libvirt.org or similar for free, it's a bit of a conversion effort to move the entire site as it exists into a wiki structure - so maybe it would be progressive i.e. new documentation goes into the wiki It would be a lot of admin i'm sure, keeping rubbish posts out - it would take time to configure, time which I don't unfortunately have at the moment although will hopefully have in a couple of months. If someone wants to take it on and finds RHEL4 too restrictive as described, I can provide a php5/mysql5 web enabled shell for freebies (perhaps an acknowledgement) Henri Daniel Veillard wrote:
On Mon, Apr 07, 2008 at 05:38:48PM +0100, Richard W.M. Jones wrote:
On Mon, Apr 07, 2008 at 11:47:37AM -0400, Daniel Veillard wrote:
My previous experience hosting a Wiki on xmlsoft.org (a.k.a. libvirt.org) has been rather painful, admitedly that was a few years ago ... I'm not sure what's the best way, hosting yet another wiki or reusing an existing one.
Wikis, as you point out, require active management.
I'm running several low-traffic OCaml wikis (might as well advertise them: http://ocaml-tutorial.org/ and http://cocan.org/) with reasonable success. We require authenticated email addresses for all editing, a diff of all edits are CC'd daily to subscribers, and we have people who act as editors for particular pages / sections of the wiki.
This has controlled spam reasonably successfully. One Ubuntu developer who shall remain nameless turned out to have a sideline in blackhat "SEO" (wiki spamming) and actually signed up with his valid email address to spam the wiki. This was spotted almost instantly and he was kicked off. We had another case where someone signed up using http://mailinator.com and set up a http://bugmenot.com account which we also found quickly and eliminated. The daily emailed diffs of the whole wiki, plus the ability to roll back a day, basically make any long-term wiki spam impossible to carry out (or so we think ...[1])
The benefits of all this management can be useful, user-driven resources, and _if_ carefully structured and edited, this can be better than Google + mailing lists or asking the same questions over and over on IRC.
Well if you have maintainance experience, why not ... except libvirt.org is a RHEL-4 box, i.e. not the easiest for bleeding edge stuff. if you feel this is reasonnable, and won't waste too much time, I agree this can be really useful too, I'm fine with the idea.
Daniel
On Mon, Apr 07, 2008 at 03:35:51PM -0400, Daniel Veillard wrote:
On Mon, Apr 07, 2008 at 05:38:48PM +0100, Richard W.M. Jones wrote:
On Mon, Apr 07, 2008 at 11:47:37AM -0400, Daniel Veillard wrote:
My previous experience hosting a Wiki on xmlsoft.org (a.k.a. libvirt.org) has been rather painful, admitedly that was a few years ago ... I'm not sure what's the best way, hosting yet another wiki or reusing an existing one.
Wikis, as you point out, require active management.
I'm running several low-traffic OCaml wikis (might as well advertise them: http://ocaml-tutorial.org/ and http://cocan.org/) with reasonable success. We require authenticated email addresses for all editing, a diff of all edits are CC'd daily to subscribers, and we have people who act as editors for particular pages / sections of the wiki.
This has controlled spam reasonably successfully. One Ubuntu developer who shall remain nameless turned out to have a sideline in blackhat "SEO" (wiki spamming) and actually signed up with his valid email address to spam the wiki. This was spotted almost instantly and he was kicked off. We had another case where someone signed up using http://mailinator.com and set up a http://bugmenot.com account which we also found quickly and eliminated. The daily emailed diffs of the whole wiki, plus the ability to roll back a day, basically make any long-term wiki spam impossible to carry out (or so we think ...[1])
The benefits of all this management can be useful, user-driven resources, and _if_ carefully structured and edited, this can be better than Google + mailing lists or asking the same questions over and over on IRC.
Well if you have maintainance experience, why not ... except libvirt.org is a RHEL-4 box, i.e. not the easiest for bleeding edge stuff. if you feel this is reasonnable, and won't waste too much time, I agree this can be really useful too, I'm fine with the idea.
FYI, the et.redhat.com which hosts virt-manager.org / ovirt.org / freeipa.org is setup to provide Wikis - we can easily add a libvirt mediawiki instance there if desired. Dan. -- |: Red Hat, Engineering, Boston -o- http://people.redhat.com/berrange/ :| |: http://libvirt.org -o- http://virt-manager.org -o- http://ovirt.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: GnuPG: 7D3B9505 -o- F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :|
On Mon, Apr 07, 2008 at 09:14:03PM +0100, Daniel P. Berrange wrote:
On Mon, Apr 07, 2008 at 03:35:51PM -0400, Daniel Veillard wrote:
Well if you have maintainance experience, why not ... except libvirt.org is a RHEL-4 box, i.e. not the easiest for bleeding edge stuff. if you feel this is reasonnable, and won't waste too much time, I agree this can be really useful too, I'm fine with the idea.
FYI, the et.redhat.com which hosts virt-manager.org / ovirt.org / freeipa.org is setup to provide Wikis - we can easily add a libvirt mediawiki instance there if desired.
Thanks to Henry for his offer, but i think adding the Wiki on et.redhat.com would make a lot of sense, since it's already set up (just a bit of config seems needed) and existing people around the project can manage it. I have added wiki.libvirt.org to point to et.redhat.com, this should propagate to DNS shortly. That should allow to plug the Wiki in easilly I suppose, Daniel -- Red Hat Virtualization group http://redhat.com/virtualization/ Daniel Veillard | virtualization library http://libvirt.org/ veillard@redhat.com | libxml GNOME XML XSLT toolkit http://xmlsoft.org/ http://veillard.com/ | Rpmfind RPM search engine http://rpmfind.net/
On Mon, Apr 07, 2008 at 04:03:25PM +0100, Henri Cook wrote:
On a different tack - what about making some Wiki pages, or the pages on the main site wiki-integrated? I would love to add more info for KVM users to the XML format page, there were a lot of things i had to trial and error figure out myself when importing a) DomUs from a past Xen Install and b) DomUs from kvm command-line only setups
As part of the Web site update/cleanup by Dan, there is now a wiki for libvirt, see http://wiki.libvirt.org/ it's linked from the main site. Tell us if there is any problem, thanks, Daniel -- Red Hat Virtualization group http://redhat.com/virtualization/ Daniel Veillard | virtualization library http://libvirt.org/ veillard@redhat.com | libxml GNOME XML XSLT toolkit http://xmlsoft.org/ http://veillard.com/ | Rpmfind RPM search engine http://rpmfind.net/
Brilliant, I really like the look of the site now! I look forward to contributing in the future Henri Daniel Veillard wrote:
On Mon, Apr 07, 2008 at 04:03:25PM +0100, Henri Cook wrote:
On a different tack - what about making some Wiki pages, or the pages on the main site wiki-integrated? I would love to add more info for KVM users to the XML format page, there were a lot of things i had to trial and error figure out myself when importing a) DomUs from a past Xen Install and b) DomUs from kvm command-line only setups
As part of the Web site update/cleanup by Dan, there is now a wiki for libvirt, see http://wiki.libvirt.org/ it's linked from the main site. Tell us if there is any problem,
thanks,
Daniel
participants (4)
-
Daniel P. Berrange -
Daniel Veillard -
Henri Cook -
Richard W.M. Jones